Manufacture of steel



possessing alloy according Patented Nov. 14, 1922.

states rarest.

BO BERT ABBOTT HADFIEIiD, OF WESTMINSTER, ENGLAND.

I MANUFACTURE OF STEEL.

No Drawing. Application filed July 15, 1916,

Be it known that I, Sir ROBERT ABBOTT HADFIELD, F. .R. S., a subject of the King of Great Britain and Ireland, residing'at Westminster, England, have invented new or improved following is a specification. I

This invention has for its object the manufacture of a manganese steel or iron alloy amongst other qualities, great toughness and resistance to perforation, particularly when in the form of heat treated sheets or plates.

I have found that this object can be attained by using an alloy of iron, carbon, silicon, manganese and copper. The copper may be added to an alloy of iron, carbon, silicon and manganese of the kind ordinarily known as manganese steel which usually contains a Small percentage of silicon, seldom exceeding 3%. When the desired percentage of silicon in an alloy of this kind is not sufficiently high for any desired to the invention, and usually a higher percentage, say from about .6 to 2% will be necessary to obtain the best results, additional silicon must be added to the alloy referred to in addition to the copper. Such a percentage high in relation to that usually existing in ordinary manganese steel.

The new alloy of iron, carbon, silicon, manganese and copper which forms a new manganese steel, may vary in the percentage composition of its constituents, but the percentage of manganese will always be high relatively to the other constituents except the i iron. It may for example comprise iron with about from .9 to 2% of carbon, with from about .1 to 2% or above of silicon, with from about 10 to 15% or it may be up to- 17% of manganese and from about 1 to 3 or 4% of copper, but the invention is not limited to these. percentages, the main feature of the new steel or alloy being the presence therein of silicon and copper. The copper, and also the silicon,- when an additional quantity thereof is used, maybe added to ordinary manganese steel when in the molten state, or to themixture of iron and ferro-manganese, or iron and manganese, used to produce such ordinary manganese steel, and melted simultaneously therewith, the 'resulting new manganese steel being cast into ingots or other castings.

Manufacture of Steel, of which the of silicon is relatively I bon,

The

copper may be added as such, or in any other suitable form. When additional silicon is used, it may be added as 'such'or in any other suitable or convenient'form, as for example as ferro-silicon or silicon spiegel.

The quality of the new manganese steel or iron alloy can be improved, at least for some purposes, by subjecting -it to a toughening process consisting in heating it to a high temperature, say for example to about 900 C. and up to it may be 1050" C. or above but below its melting point, and cooling it quickly, as by quenching it in water. The new steel or alloy when thus heat treated and water quenched, usually called water toughened, has a greater toughness and resistance to perforation than ordinary man ganese steel of commerce.

For many purposes, the new steel or alloy may advantageously be rolled into the form of sheets or plates (hereinafter referred to as sheets), or of rods, bars or wire, and be subjected to the toughening process referredto, when in such form, or previously, as when in the form of ingots or slabs. If desired, the toughening process may be repeated. The new steel or alloy can also be used for castings of any desired shape and be heat treated or not as may be required.

Another element, such for example as chromium, nickel, cobalt, vanadium, tungsten,-titanium or aluminium, or two or more of such elements, may be added to the new steel or alloy for the purpose of improving or varying the centage of such element or elements employed is such as to give to the resulting steel or iron alloy the varying desired qualities.

By way of example, it may be stated that good results have been obtained with a steel or iron alloy according to the invention and in the form of water toughened plates or sheets, when containing about 35% about 1.25% of silicon, about 12.72% of manganese and about 1.44% of copper and also .with a steel or iron alloy containing about 1.24% of carbon, about .11% silicon,

of copper.

of car-' quality thereof. The per- The new steel or iron alloy can be used for various purposes and in either the rolled, fdrged or cast condition.

What I claim is 1. A steel alloy containing from about two per cent and upwards of manganese, from about seven tenths per cent up to about two per cent of carbon, a substantial amount of copper, and from one tenth per cent and upwards of silicon.

2. A steel alloy containing from about. ten per cent and upwards of manganese, carbon up to two per cent, copper up to four per cent and silicon up to two per cent.

3. A steel alloy containing from about ten per cent and upwards of manganese, from about one to four per cent of copper and from aboutone tenth per cent to about two per cent of silicon.

.4. A steel allo containing from about ten per cent an upwards of manganese from about seven tenths per cent to two per cent of carbon, from about one to four per cent of copper and from about one tenth per cent to about two per cent of silicon.

5. A steel alloy containingover ten per cent of manganese, over 'one per cent of copper and from one tenth of one per cent to about two per cent of silicon.

6. A steel alloy containing over ten per cent of manganese, over one per cent of copper and a substantial amount of silicon.

7.. A steel alloy having great resistance to perforation and great toughness, and containing from about. one tenth of oneper centto about two per cent of carbon, from about ten to about seventeen per cent of manganese, from about one to about four per cent of copper, and from about one tenth of one percent to about two per cent of silicon. v

8. A steel alloy containing from about twelve to thirteen per cent of manganese, from about nine tenths per cent to about one decimal five per' cent of carbon, from about .one per. cent to one decimal five per cent of copper, and from about one tenth per cent to about one decimal five per cent of silicon.

9. Manganese steel containing from about one to four per cent of copper and a substantial amount of silicon.

10. A steel alloy containing manganese from about ten per cent and upwards, car-.

bon up to about two per cent, copper up to four per cent and silicon up to two per cent and treated by heat above about 900 C. and below its melting point and then cooled quickly.

toughness and resistance to perforat on and containing from about one to four per cent of copper and a substantial amount of sili- I COIL about .9 to about 1.50 per cent, manganese from about ten to about seventeen per cent, copper from about one to about four per cent 13. A steel alloy containing carbon from and silicon from about one tenth per cent to about two per cent, and treated by heat above about 900 C. and below'its melting point, and then cooled quickly.

' 14:. As a new article of manufacture, steel having great toughness and resistance to perforation and containing from about ten to seventeen per cent of. manganese, from about seven tenths per cent to one and five tenths per cent of carbon, a substantial amount of copper and from about five tenths per cent to two per cent of silicon. V

15. As a new article of manufacturmman' ganese steel in wrought form and alloyed with from about one to four per cent of copper and a substantial amount of silicon and treated by heat to above about 900 C. and below its melting point and then cooled quickly. v

16. As a new article of manufacture, manganese steel in sheet form alloyed with from about one per cent to fourper cent of copper and a substantial amount of silicon up to about two* per cent and treated by heat to above about 900 C. and below its melting ROBERT ABBOTT HADFIELD.

Witnesses:

WILLIAM Cnoss JOHN HAROLD HM 1a. 

